The intruders drove through a security checkpoint at the main gate about 9 p.m., and failed to heed guards’ orders, base officials said late Sunday in a statement.
Barriers were deployed, according to the statement. The vehicle was stopped, but two people fled, the base said.
As of 11 p.m. Sunday, the whereabouts of the second intruder remained unknown, according to the statement, and the main gate to the base remained closed.
The incident appeared to be one of the most serious breaches of security in memory at Andrews, which is a few miles outside Washington, in the Suitland area of suburban Prince George’s County, Md.
It was unclear late Sunday what motivated the incident, and why the intruders entered the base.
Harris and several Cabinet members had traveled to Selma, Ala., to commemorate the anniversary of Bloody Sunday, in which police attacked peaceful protesters in 1965. They left Alabama on Air Force Two about 6:45 p.m. Sunday and landed in Maryland about 9 p.m.
A White House official confirmed by about 9:40 p.m. that all four Cabinet secretaries — Transportation Secretary Pete Buttigieg, Housing Secretary Marcia L. Fudge, Education Secretary Miguel Cardona and Environmental Protection Agency Administrator Michael Regan — left the base safely.
A report of the “armed individual on base” was sent at 9:06 p.m. via NPR’s Scott Detrow, who was traveling with the group. The president was not at Joint Base Andrews on Sunday because he traveled directly from Delaware to the White House via a helicopter.
Harris departed via Marine Two before the report was made public, according to reports from journalists traveling with Harris that were confirmed by the vice president’s office.